The culture of the Islamic Iran, that had already begun to collapse since the 5th and 6th Centuries AH faced almost total deterioration in the early 7th Century AH/13th Century AD. This phenomenon can be said to have come about because philosophical intellectualism had come to be replaced by religious arguments and because the intellect was put at the service of religious dogmatism. At this point in the history of Iran only that branch of knowledge was allowed to prevail that could serve the religious interests of the anti-intellect elements. Following the devastating Mongol invasion of Iran, India and Rome (Asia Minor) replaced Khorāsān as the most important centers of the Islamic Iranian culture where it was patronized and protected. Nevertheless, Iranian culture and literature continued to survive in two places within of Iran viz. Fārs and the Esmā’ili forts. With the submission of Jalāl al-Din - a new convert to Islam - to the Mongol rule, the Esmā’ili forts had served for nearly forty years as the only sanctuary for scholars who had been forced to leave their hometowns at the outbreak of the Mongol invasion. Moreover, the presence of Khwājeh Nasir al-Din Tusi in the Esmā’ili forts and his migration to Marāgheh - the main center of the Mongol ruler, Hulagu Khan - throw light on the role of the Esmā’ili forts in this regard. Consequently, at this point we shall need to follow the history of theology by first glancing through the school of the Esmā’ili forts and then looking at the Marāgheh, Shirāz, Esfahān, Tehran, and Qom schools until the present times.